The present invention relates to a seal assembly for sealing a rotating shaft to a stationary housing such as sealing a pump shaft to a pump casing. The mechanical seal typically provides one or two pairs of seal rings, one of each pair being stationary with respect to said housing and the respective other of said seal rings being mounted for rotation with the shaft and having face contact with its respective matched stationary seal ring. When two such pairs of seal rings are used, a volume between the seal rings may be flushed with a barrier fluid to quench the seal as well as providing a secondary source of sealing and/or a source of lubrication.
In a seal arrangement such as disclosed in U.S. Pat. No. 5,116,066, an outboard seal assembly A and an inboard seal assembly B are shown in FIG. 4. A volume between the seals can be flushed with quench fluid. The rotating seal faces rotate with the pump shaft. To accomplish this, a sleeve is mounted tightly around the shaft and fixed thereto by a lock ring with set screws. One rotating ring is held within a holder which is fixed for rotation with the sleeve by a plurality of balls which are captured within spherical cavities in the sleeve and within an axial groove formed in the holder, or within a second hemispherical cavity in a set screw of the second rotating seal face holder.
U.S. Pat. No. 4,377,290 discloses a double seal arrangement wherein the rotating seal rings are locked to a flange 52 extending upward from a shaft sleeve by a pin to constrain the rotating sealing ring for rotation with the shaft.
U.S. Pat. No. 3,356,378 discloses the locking of a rotary sealing ring to a backing ring by an encircling mounting ring having one or more keys which causes the rotary sealing ring, the mounting ring, a bellows subassembly, and a shaft sleeve to rotate with the shaft.
U.S. Pat. No. 3,715,169 uses a bushing surrounding the shaft and locked thereto for rotation by a threaded plug 31, wherein the bushing is locked to another bushing which holds the rotating seal ring, the bushing, the other bushing and the seal ring 42 held together by axially arranged pins.
U.S. Pat. No. 2,247,505 discloses a shaft 10 having an annular collar secured thereto by set screws. A rotatable sealing member is locked for rotation with the annular collar by a plurality of radially extending pins 20.
A locking tab arrangement formed with a shaft sleeve for locking rotary seal rings is not disclosed.